Enablex works by blocking a chemical messenger that makes the bladder muscle contract.

In clinical trials, the most common side effects of Enablex were dry mouth and constipation. Most side effects were mild or moderate and happened during the first two weeks of treatment. Most patients who had these side effects did not have to discontinue treatment.

Some people should not take Enablex: those with urinary retention, gastric retention, or uncontrolled narrow-angle glaucoma. People at risk of these conditions should also avoid the drug.

According to a Novartis news release, some 33 million Americans suffer from overactive bladder.

"Millions of patients and their families can be profoundly affected by overactive bladder," Nancy Muller, executive director of the National Association for Continence, says in the news release. "It is important that we continue to advance technology to bring new options to people with overactive bladder to help them manage this condition."